1. Field of the Invention
The present invention relates to an adapter member for connecting a self-drilling rock anchor with a chuck of a drilling tool and including a sleeve-shaped section having a coupling section for connection with the chuck, and a bottom provided at an end of the sleeve-shaped section for forming a receiving space for connection with an end of the rock anchor and having a through-opening through which a feeding nose is extendable.
2. Description of the Prior Art
Self-drilling rock anchors, in particular chemical connection anchors and suitable drilling tools with rotatable chucks, and their use in mine and tunnel constructions are well known since long ago. The rock anchors serve primarily for stabilizing walls and hollow spaces in mines, tunnels, galleries, and the like. When hollow spaces are formed, mechanical properties and, in particular, the bearing capacity of strata are reduced. These strata are anchored to lying further, undamaged strata with rock anchors, e.g., chemical connection anchors, and are, thus, secured thereto.
The self-drilling rock anchor includes an anchor tube that functions, on one hand, as a drill rod and, on the other hand, when formed as a chemical connection anchor, as a receptacle for a to-be-pressed out mass. A drill head is provided at a first, facing in the setting direction, end of the anchor tube. The second end of the anchor tube is inserted into a chuck of a drilling tool with which the rock anchor is set into a constructional component. After completion of a drilling process, with the rock anchor being formed as a chemical connection anchor, the second end of the anchor tube is connected to a suitable squeezing-out device, and the to-be-pressed out mass is displaced in the direction of the drilling head.
With an injection anchor such as described in German Patent DE 101 48 683 C 1, after the completion of a drilling process, a feeding device for an injection mortar is arranged on the second end of the anchor tube, and the injection mortar is injected into the borehole bottom through the anchor tube.
German Publication DE 101 36 040 A1 discloses a self-drilling rock anchor that includes an adapter member connectable with the second end of the anchor tube. The adapter member includes a sleeve-shaped section having a located outside coupling section for connection with the chuck of a drilling tool, and a bottom provided at an end of the sleeve-shaped section for forming a receiving space for connection with a second end of the rock anchor. The bottom has a through-opening for a feeding nose that forms part of a feeding device and through which medium is fed in the self-drilling rock anchor.
German Patent DE 197 00 701 C2 discloses a drilling tool with a chuck and a feeding nose for feeding rinsing means into the self-drilling rock anchor. In order to prevent leakage of the fed rinsing means in the region of the chuck or in the region of medium feeding and in order to prevent any damage of the drilling tool, there are provided, in the drilling tool, several seals. The drawback of this solution consists in that the seals in particular, which come in a contact with the self-drilling anchor, are subjected to a very high wear. As a result of a displacement force of a movable support of the drilling tool that acts on the drilling tool during the drilling process, the surface pressure applied to separate seals is very high, and the seals should be replaced already after several setting processes. The replacement of a worn seal can be a very tedious process, in particular, at an existing conditions (e.g., space relationships).
Accordingly, an object of the present invention is to provide a self-drilling rock anchor that, on one hand, would insure a satisfactory sealing for the media, which are fed to the rock anchor, and, on the other hand, would be user-friendly.